Adaptive transmitter/receiver

ABSTRACT

There is provided an adaptive transceiver device which estimates a path arrival direction of a desired wave signal by using a reception antenna weight of a k-th user adaptive reception unit using a control method based on the minimum mean square error (MMSE) standards and which generates a transmission antenna weight on the basis of the path arrival direction. The adaptive transceiver device is characterized in that in reception, a directivity pattern for suppressing interference caused by another user or a multi-path is formed, an arrival direction of a path is estimated from the reception antenna weight, and a transmission direction is predicted from the estimated arrival direction to generate a transmission antenna weight, and in transmission, a directivity pattern for decreasing interference to another user is formed and transmitted.

This application is a 371 of PCT/JP99/03478 filed on Jun. 29, 1999.

TECHNICAL FIELD

The present invention relates to an adaptive transceiver device for basestation which removes interference caused by another user in receptionand which decreases interference to another user in transmission byantenna directivity control and, more particularly, to an adaptivetransceiver device using the CDMA (Code Division Multiple Access)system.

BACKGROUND ART

In recent years, in a cellular mobile communication system or the like,as a radio transmission method which can use a large number of channelsin the same frequency band so that a large scriber's capacity can beexpected, the CDMA (Code Division Multiple Access) system has beenwidely noticed. On the other hand, an adaptive transceiver device inwhich interference from another user or an interference caused by adelay wave is removed in transmission by using an adaptive antenna as anantenna for base station and in which no interface is given to anotheruser in transmission has been greatly discussed.

In addition, as an adaptive transceiver device which is appropriate tothe CDMA system, a system which controls a directional antenna usingsuch a directivity pattern that an antenna gain is maximum with respectto an arrival direction to perform transmission and reception has beenproposed.

FIGS. 7A and 7B (to be referred to as FIG. 7 hereinafter) are blockdiagrams showing an example of a k-th user adaptive transceiver devicein a base station using the conventional DS (Direction Sequence)-CDMAsystem. FIG. 8 is a block diagram showing an m-th path adaptivereception sub-block 36 m of the conventional k-th user adaptivetransceiver device shown in FIG. 7. FIG. 9 is a block diagram showing anm-th adaptive transmission sub-block 10 m of the conventional k-th useradaptive transceiver device shown in FIG. 7. Here, these drawings showan adaptive transceiver device (CDMA adaptive transceiver device) havinga configuration defined as described below. That is, the number oftransmission/reception antennas is represented N (N is an integer whichis 1 or more), the number of users is represented by K (K is an integerwhich is 1 or more), and the number of multi-paths and the number oftransmission paths per user are represented by M (M is an integer whichis 1 or more).

The conventional k-th user adaptive transceiver device is constituted bya second path search circuit 34, a second k-th user adaptive receptionunit 35, a first arrival direction estimation circuit 37, receptionantenna weight generation circuits 381 to 38M, transmission antennaweight generation circuits 301 to 30M, and a k-th user adaptivetransmission unit 9.

N antenna reception signals 1 to N are signals obtained by performingcode multiplexing to a desired wave signal and a plurality ofinterference wave signals received by N antenna elements arranged andclosed to each other such that the respective reception signals arecorrelative to each other. Since the following processes are digitallyperformed in a base band, it is assumed that the frequencies of the Nantenna reception signals 1 to N are converted from a radio band to abase band, and that the N antenna reception signals 1 to N are subjectedto analog-to-digital conversion.

The second path search circuit 34 calculates pieces of path delay timeinformation D1 to DM of a desired wave signal of the k-th user from thereception signals multiplexed by a plurality of user signals.

The second k-th user adaptive reception unit 35 is constituted by firstdelay circuits 31 to 3M, second m-th path adaptive reception sub-blocks361 to 36M, and a first adder 5.

The first delay circuits 31 to 3M delay the N antenna reception signals1 to N depending on a multi-path on the basis of the pieces of pathdelay time information D1 to DM of a desired wave signal which is anoutput from the second path search circuit 34.

The first adder 5 adds outputs from the second m-th path adaptivereception sub-blocks 361 to 36M to each other to output a k-th userdemodulation signal.

The second m-th path adaptive reception sub-blocks 361 to 36M, as shownin FIG. 8, is constituted by despreading circuits 121 to 12M, areception weighting combining unit 13, and a demodulation unit 16. Thesecond m-th path adaptive reception sub-blocks 361 to 36M receives theantenna reception signals 1 to N and m-th reception antenna weights Wr1to WrM which are outputs from reception antenna weight generationcircuits 381 to 38M.

Despreading circuits 121 to 12N perform a correlative calculation of theantenna reception signals 1 to N and a pseudo random code Ck. It isassumed that the pseudo random code Ck is a complex code consisting oftwo codes CkI and CkQ which are orthogonal to each other. In this case,each of the despreading circuits 121 to 12N can be realized by onecomplex multiplier and an averaging circuit operating over a symbolsection. Each of the despreading circuits 121 to 12N can also berealized by a transversal filter configuration using the code Ck as atap weight.

The reception weighting combining unit 13 is constituted by firstcomplex multipliers 141 to 14N and a second adder 15. The outputs fromthe despreading circuits 121 to 12N are multiplied by m-th receptionantenna weights Wm1 to WmN, respectively, and the resultant values aresummed up, so that the received signal is generated by an antennadirectivity pattern inherent in the m-th path.

A demodulation unit 16 is constituted by a transmission path estimationcircuit 17 and a second complex multiplier 18. An output obtained bymultiplying an output from the reception weighting combining unit, 13 bya complex conjugate of transmission path estimation outputs serves as anoutput from the second m-th path adaptive reception sub-block 36 m.

Outputs from the second m-th path adaptive reception sub-block 36 m areadded to each other by the adder 5, and an output from the adder 5serves as a demodulated signal from the k-th user.

Next, the first arrival direction estimation circuit 37 receives Nantenna reception signals 1 to N as inputs, and estimates the arrivaldirection of M desired wave signals of the k-th user from receptionsignals multiplexed by a plurality of user signals. As a method ofestimating an arrival direction, e.g., the MUSIC method is known.

The M m-th reception antenna weight generation circuits 381 to 38Mcalculate m-th reception antenna weights (steering vectors) Wr1 to WrMfor forming directivity patterns having gains in a desired signalarrival direction on the basis of M estimated arrival directions θr1 toθrM which are outputs from the first arrival direction estimationcircuit 37.

The M m-th transmission antenna weight generation circuits 301 to 30Mcalculate m-th transmission antenna weights (steering vectors) Wt1 toWtM for forming directivity patterns having gains in a user transmissiondirection which is the same as the desired signal arrival direction onthe basis of the M estimated arrival directions θn1 to θrM which are theoutputs from the first arrival direction estimation circuit 37.

When the FDD (Frequency Division Duplex) method is used, a frequency inreception is different from a frequency in transmission. For thisreason, a reception antenna weight and a transmission antenna weightmust be independently determined on the basis of the estimated arrivaldirection. When the TDD (Time Division Duplex) method, a frequency inreception is equal to a frequency in transmission. For this reason, areception antenna weight can also be directly employed as a transmissionantenna weight.

The k-th user adaptive transmission unit 9 is constituted by the m-thadaptive transmission sub-blocks 101 to 10M and the third adders 111 to11N.

The third adders 111 to 11N synthesize outputs from the m-th adaptivetransmission sub-blocks 101 to 10M with each other for N transmissionantennas, and outputs N synthesized antenna transmission signals 1 to N.The N synthesized antenna reception signals 1 to N are subjected todigital/analog conversion. The frequencies of the N synthesized antennareception signals 1 to N are converted from a base band to a radio band.

Each of the first adaptive transmission sub-blocks 101 to 10M, as shownin FIG. 9, is constituted by a transmission weighting combining unit 31and spreading circuits 331 to 33N. The m-th adaptive transmissionsub-blocks 101 to 10M receive m-th reception antenna weight Wtm (Wtm1 toWtmM) which are outputs from the M transmission antenna weightgeneration circuits 301 to 30M and a k-th user transmission signal.

The transmission weighting combining unit 31 is constituted by fourthcomplex multipliers 321 to 32N. The k-th user transmission signal ismultiplied by the m-th transmission antenna weight Wtm (Wtm1 to WtnN) togenerate a signal transmitted by an antenna directivity pattern inherentin the m-th path.

The spreading circuits 331 to 33N diffuses N outputs from thetransmission weighting combining unit 31 by using the pseudo random codeCk of the k-th user to generate N antenna transmission signals 1 to N.When the pseudo random code Ck is considered as a complex codeconsisting of two codes CkI and CkQ which are orthogonal to each other,each of the spreading circuits 331 to 33N is realized by one complexmultiplier and an averaging circuit operating over a symbol section.Each of the spreading circuits 331 to 33N can also be realized by atransversal filter configuration using the code Ck as a tap weight.

The N antenna reception signals 1 to N include desired wave signalcomponents, interference wave signal components, and thermal noise. Inaddition, the desired wave signal component and the interference wavesignal component include multi-path components. In general, these signalcomponents are arrived from different directions. The conventional CDMAadaptive transceiver device shown in FIGS. 7 to 9 prepares the firstarrival direction estimation circuit 37 to estimate the arrivaldirections of the multi-paths of desired signals, weighting combining ofa reception signal in the reception weighting combining unit 13 andweighting combining of a transmission signal in the transmissionweighting combining unit 31 are performed such that the signal powers ofthe paths are maximized. As a result, antenna gains (directivitypatterns) of the second m-th path adaptive reception sub-blocks 361 to36M and the m-th adaptive transmission sub-blocks 101 to 10M are formedto be increased with respect to the arrival directions of themulti-paths of the desired signals in reception.

When the FDD (Frequency Division Duplex) method is used, a frequency inreception is different from a frequency in transmission. For thisreason, a reception antenna weight and a transmission antenna weightmust be independently determined on the basis of the estimated arrivaldirection. When the TDD (Time Division Duplex) method, a frequency inreception is equal to a frequency in transmission. For this reason, areception antenna weight can also be directly employed as a transmissionantenna weight.

As a receiver device using an adaptive antenna appropriate to the CDMAsystem, a device obtained by a spectrum spreading process gain isproposed. Conventionally, the CDMA adaptive receiver device of thistype, as described in “Wang, Kohno, and Imai, “Adaptive Array AntennaCombined with Trapped Delay Line Using Processing Gain forDirect-Sequence/Spread-Spectrum Multiple Access System”, ShingakuronVol. J75-B-II No. 11, pp 815–825, 1992”, “Tanaka, Miki, and Sawahashi,“The Performance of Decision-Directed Coherent Adaptive Diversity inDS-CDMA Reverse Link”, TECHNICAL REPORT OF IEICE. RC596-102, 1996-11”,in reception antenna weight control, a weight control error signalextracted after despreading is used to obtain an SINR improvement effectobtained by a process gain in adaptive control.

FIG. 10 is a block diagram showing another example of the conventionalk-th user adaptive receiver device. FIG. 11 is a block diagram showingan m-th path adaptive reception sub-block 40 m of the conventional k-thuser adaptive transceiver device shown in FIG. 10. Here, these drawingsshow a k-th user adaptive receiver device (CDMA adaptive transceiverdevice) having a configuration defined as described below. That is, thenumber of transmission/reception antennas is represented N (N is aninteger which is 1 or more), the number of users is represented by K (Kis an integer which is 1 or more), and the number of multi-paths and thenumber of transmission paths per user are represented by M (M is aninteger which is 1 or more).

The conventional k-th user adaptive receiver device is constituted by asecond path search circuit 34 and a third k-th user adaptive receptionunit 39.

The N antenna reception signals 1 to N are signals obtained byperforming code multiplexing to a desired wave signal and a plurality ofinterference wave signals received by N antennas arranged and closed toeach other such that the respective reception signals are correlative toeach other. Since the following processes are digitally performed in abase band, it is assumed that the frequencies of the N antenna receptionsignals 1 to N are converted from a radio band to a base band, and thatthe N antenna reception signals 1 to N are subjected to analog/digitalconversion.

The second path search circuit 34 calculates pieces of path delay timeinformation D1 to DM of a desired wave signal of the k-th user from thereception signals multiplexed by a plurality of user signals.

The third k-th user adaptive reception unit 39 is constituted by firstdelay circuits 31 to 3M, third m-th path adaptive reception sub-blocks401 to 40M, a first adder 5, and a decision circuit 6.

The first delay circuits 31 to 3M delay N antenna reception signals 1 toN depending on a multi-path on the basis of pieces of path delay timeinformation D1 to DM of a desired wave signal which is an output fromthe second path search circuit 34.

The first adder 5 adds outputs from the third m-th path adaptivereception sub-blocks 401 to 40M to each other to output a k-th userdemodulation signal.

The decision circuit 6 performs hard decision to an output from thefirst adder 5 to output a k-th user decision symbol.

Each of the third m-th path adaptive reception sub-blocks 401 to 40M isconstituted by despreading circuits 121 to 12M, a reception weightingcombining unit 13, a demodulation unit 16, a third complex multiplier19, an error detection circuit 20, a second delay circuit 21, and areception antenna weight control circuit 22. The third m-th pathadaptive reception sub-blocks 401 to 40M receive antenna receptionsignals 1 to N and a k-th user decision symbol which is an output fromthe decision circuit 6.

The despreading circuits 121 to 12N perform correlative calculationbetween the antenna reception signals 1 to N delayed by the first delaycircuits 31 to 3M and the pseudo random code Ck of the k-th user. Whenthe pseudo random code Ck is considered as a complex code consisting oftwo codes CkI and CkQ which are orthogonal to each other, each of thedespreading circuits 121 to 12N is realized by one complex multiplierand an averaging circuit operating over a symbol section. Each of thedespreading circuits 121 to 12N can also be realized by a transversalfilter configuration using the code Ck as a tap weight.

The reception weighting combining unit 13 is constituted by firstcomplex multipliers 141 to 14N and a second adder 15. The outputs fromthe despreading circuits 121 to 12N are multiplied by m-th receptionantenna weights Wm1 to WmN, respectively, and the resultant values aresummed up, so that the received signal is generated by an antennadirectivity pattern inherent in the m-th path.

The demodulation unit 16 is constituted by a transmission pathestimation circuit 17 and a second complex multiplier 18. An outputobtained by multiplying an output from the reception weighting combiningunit 13 by a complex conjugate of transmission path estimation outputsserves as an output from the third m-th path adaptive receptionsub-block 40 m.

The third complex multiplier 19 multiplies the transmission pathestimation output by the k-th user decision symbol.

When the k-th user decision symbol is multiplied by transmission pathestimation values of the respective paths, only components related tothe phases of the estimation values can be multiplied, and amplitudescalculated by another means may also be multiplied. Another meansindicates such a means that a reception power is measured to calculatean amplitude.

The error detection circuit 20 calculates the difference between anoutput from the third complex multiplier 19 and an output from thereception weighting combining unit 13 to detect a reception antennaweight control error em.

The second delay circuit 21 delays outputs from the despreading circuits121 to 12N depending on process times of the reception weightingcombining unit 13, the demodulation circuit 16, the error detectioncircuit 20, and the like.

The reception antenna weight control circuit 22 calculates receptionantenna weights Wm1 to WmN from a reception antenna weight control errorem and an output from the second delay circuit 21.

In a convergence process of adaptive control, a known symbol may also beused in place of the decision symbol.

The N antenna reception signals 1 to N include desired wave signalcomponents, interference wave signal components, and thermal noise. Inaddition, the desired wave signal component and the interference wavesignal component include multi-path components, respectively. Ingeneral, these signal components are arrived from different directions.In the conventional CDMA adaptive transceiver device shown in FIGS. 9and 10, the third m-th path adaptive reception sub-blocks 401 to 40M areindependently prepared for the multi-path components of the desired wavesignals, and weighting combining of reception signals are performed inthe reception weighting combining units 13 such that a ratio of thedesired wave signals of the signal components of the respective paths toan interference wave signal power (SIR) is maximized. As a result, theantenna gains (directivity pattern) of the third m-th path adaptivereception sub-blocks 401 to 40M with respect to arrival directions areformed such that the antenna gains are increased with respect to thearrival directions of the signal components of the respective paths anddecreased with respect to other delay wave signal components and theinterference wave signal component.

As a method of controlling a reception antenna weight which maximizesthe ratio of the desired wave signals to an interference wave signalpower (SIR), a method of controlling a reception antenna weight on thebasis of the MMSE (Minimum Mean Square Error) standards such that theaverage power of the reception antenna weight control error em isminimized. In the control method based on the MMSE standards, a patharrival direction of a desired wave signal need not be known, and thepath arrival direction of the desired wave signal cannot be directlyknown. Therefore, in order to generate transmission antenna weight forforming a transmission direct ivity pattern as in the conventional CDMAadaptive transceiver device shown in FIGS. 7 to 9, another means forestimating the path arrival direction of the desired wave signal isrequired.

Here, as adaptive control performed by the MMSE standards, for example,an LMS (Least Mean Square) algorithm is cited.

However, the first disadvantage of the conventional technique is asfollows. In the reception unit of the conventional k-th user adaptivetransceiver device shown in FIGS. 7 to 9, control for forming adirectivity pattern which actively decreases a gain with respect to aninterference wave cannot be performed, and performance is poorer thanthat in the control based on the MMSE standards.

More specifically, in the k-th user adaptive reception unit, receptionweighting combining is performed by using an antenna weight appropriateto only the path arrival direction of the estimated desired wave signal.

The second disadvantage is as follows. When the conventional k-th useradaptive receiver device for performing control based on the MMSEstandards shorn in FIGS. 10 to 11 is used as an adaptive transceiverdevice, especially, in the FDD method, a desired wave arrival directionestimation means for calculating a transmission antenna weight must beprepared independently of the reception unit, and the device increasesin scale. More specifically, in the k-th user adaptive reception unitusing a control method based on the MMSE standards, the path arrivaldirection of a desired wave signal cannot be directly known.

In the TDD method, the reception antenna weight controlled on the basisof the MMSE standards can be directly used as a transmission antennaweight. In addition, when transmission and reception are controlled onthe basis of an arrival direction estimation result, performance in thereception is not poor. On the other hand, when control based on the MMSEstandards is performed on the reception side, another arrival directionestimation means for transmission is required, and the structuredisadvantageously increases in size.

Therefore, it is an object of the present invention to provide a meansfor estimating the path arrival direction of a desired wave signal byusing a reception antenna weight of a k-th user adaptive reception unitusing a control method based on the MMSE standards and generating atransmission antenna weight on the basis of the path arrival direction.

DISCLOSURE OF THE INVENTION

An adaptive transceiver device according to the present invention formsa directivity pattern for suppressing interference caused by anotheruser or a multi-path in reception, estimates an arrival direction of apath from a reception antenna weight, predicts a transmission directionfrom the estimated arrival direction to generate a transmission antennaweight, and forms a directivity pattern for decreasing interference toanother user in transmission.

An adaptive transceiver device of a DS-CDMA system according to thepresent invention is characterized by including: path search means forcalculating path level information and path delay time information froman antenna reception signal; M (M is a positive integer) adaptivereception units for receiving N (N is a positive integer) antennareception signals, forming reception directivity patterns each having again in the direction of a desired wave signal every path delay time,receiving the desired wave signals, and suppressing interference wavesignals; reception antenna weight selection means for selectingreception antenna weights for L (L is an integer equal to or smallerthan M) transmission paths from the M reception antenna weights by usingthe path level information; L transmission antenna weight control unitsfor determining transmission antenna weights for forming transmissiondirectivity patterns by using outputs from the reception antenna weightselection means; and an adaptive transmission unit for forming thetransmission directivity pattern having a gain in a user direction byusing the transmission antenna weight which is an output from thetransmission antenna weight control unit and outputting N combiningantenna transmission signals for transmitting the desired wave signal.

It is a point according to the present invention that the transmissionantenna weight is determined by using only the reception antenna weightof the adaptive reception unit (without using other information).

The adaptive transceiver device according to the present invention ischaracterized in that the adaptive reception unit has: M delay meanswhich receive the N antenna reception signals and the path delay timeinformation which is an output from the path search means and whichmatch timings depending on the path delay times of M multi-paths; Madaptive reception sub-blocks for forming the reception directivitypatterns having gains in the directions of the M multi-paths,suppressing the interference wave signal, and receiving and demodulatingthe desired wave signal; an adder for synthesizing M demodulationsignals; and decision means for performing hard decision to output adecision symbol.

According to the present invention, timings are matched on the basis ofthe path delay time, a directivity pattern is formed every multi-path,and combining (RAKE reception) is finally performed.

In addition, the present invention is characterized in that the antennareception signal is a CDMA (Code Division Multiple Access) signal, eachof the M adaptive reception sub-blocks has: N despreading means whichreceive the N antenna reception signals and the decision symbol andwhich performs despreading to each of the N antenna reception signals byusing a pseudo random code of the desired wave signal; a receptionweighting combining unit for forming the reception directivity pattern;a demodulation unit for performing the transmission path estimation; amultiplier for multiplying the decision symbol by a complex transmissionpath estimation value which is an output from the demodulation unit tocancel a phase change caused by carrier wave phase synchronization;error detection means for subtracting each output from the despreadingmeans from an output from the multiplier to detect the reception antennaweight control error; delay means for delaying outputs from the Ndespreading means depending on the process times of the receptionweighting combining means, the demodulation means and the like; andreception antenna weight control means for outputting the receptionantenna weight on the basis of the minimum mean square error (MMSE)standards such that the average power of the reception antenna weightcontrol error is minimized by using an output from the delay means andthe reception antenna weight control error.

According to the present invention, a reception antenna weight iscontrolled on the basis of the MMSE standards by the m-th path adaptivesub-block. Therefore, a path arrival direction need not be known, andthe path arrival direction cannot be directly known.

Furthermore, the present invention is characterized in that thereception weighting combining unit has: N complex multipliers whichreceive the N antenna reception signals and the reception antennaweights and which multiply the reception signals by N complex receptionantenna weights; and an adder for synthesizing respective outputs fromthe N complex multipliers.

Still furthermore, the present invention is characterized in that thedemodulation means has: transmission path estimation means whichreceives an output from the weighting combining unit to estimate theamplitude and the phase of a carrier wave; complex conjugate operationmeans for calculating a complex conjugate of complex transmission pathestimation values which are output from the transmission path estimationmeans; and a multiplier for multiplying an output from the complexconjugate operation means by an output from the despreading means toperform carrier wave phase synchronization and, at the same time, toperform weighting for synthesizing a maximum ratio.

According to the present invention, the m-th path antenna weight isdetected by the m-th path adaptive sub-block.

In addition, the present invention is characterized in that thereception antenna weight selection means receives M reception antennaweights which are outputs from the M adaptive reception sub-blocks, pathlevel information which is an output from the path search means, a pathlevel threshold value, and a maximum transmission count Lmax, andselects a selection reception antenna weight corresponding to L pathsthe number of which is not larger than the maximum transmission countLmax and which has a level set within the range of the level of themaximum path to the path level threshold value from the M receptionantenna weights.

According to the present invention, Lmax is equal to or smaller than M,and L is equal to or smaller than Lmax. After some reception antennaweights having large path levels are selected, a transmission antennaweight is determined. Furthermore, when a plurality of paths areselected and transmitted, a transmission diversity effect can beobtained.

The present invention is characterized in that the transmission antennaweight control unit has: an arrival direction estimation unit whichreceives the selection reception antenna weight to estimate an estimatedarrival direction from the selection reception antenna weight; and atransmission antenna weight generation means for calculating atransmission antenna weight for forming a directivity pattern having again in the estimated arrival direction which is an output from thearrival direction estimation unit.

According to the present invention, the arrival direction is estimatedfrom the reception antenna weight. A transmission antenna weight isgenerated by directly setting the estimated arrival direction as atransmission direction. In particular, in the FDD (Frequency DivisionDuplex) method, since a frequency in reception is different from afrequency in transmission, an arrival direction is temporarily estimatedfrom the reception antenna weight, and the transmission antenna weightmust be determined on the basis of the arrival direction. In addition,in the TDD (Time Division Duplex) method, since a frequency in receptionis equal to that in transmission, a reception antenna weight can also beemployed as a transmission antenna weight.

Furthermore, the present invention is characterized in that thetransmission antenna weight control unit has: an arrival directionestimation unit which receives the selection reception antenna weight toestimate an estimated arrival direction from the selection receptionantenna weight; transmission direction prediction means for predicting atransmission direction on the basis of the estimated arrival directionwhich is an output from the arrival direction estimation unit; andtransmission antenna weight generation means for calculating atransmission antenna weight for forming a directivity pattern having again in the prediction transmission direction which is an output fromthe transmission direction prediction means.

According to the present invention, an arrival direction is estimatedfrom a reception antenna weight. A transmission direction is predictedfrom an estimated arrival direction. In addition, a predictiontransmission direction is set as a transmission direction, so that atransmission antenna weight is generated. In either one of the FDDmethod and the TDD method, a transmission direction is predicted, sothat a transmission antenna weight can be generated.

The present invention is characterized in that the arrival directionestimation unit has: arrival direction generation means which receivesthe selection reception antenna weight to sweep arrival directions overall the directions; steering vector generation means for calculating anantenna weight for forming a directivity pattern of a maximum antennagain in the arrival direction; correlative calculation means forcalculating a correlation between the selection reception antenna weightand an antenna weight which is an output from the steering vectorgeneration means; maximum value detection means for detecting themaximum value of outputs from the correlative calculation means withrespect to all the arrival directions; and switching means foroutputting the arrival direction at a point of time at which the maximumvalue is detection as an estimated arrival direction.

According to the present invention, an arrival direction is estimated byusing only a reception antenna weight. In particular, the presentinvention is preferable in the FDD method.

In addition, the present invention is characterized in that thetransmission direction prediction means predicts a present arrivaldirection by using a past arrival direction which is estimated latebecause of the control of the adaptive reception unit.

According to the present invention, by a first transmission antennaweight control unit, even in the FDD method or the TDD method, atransmission direction is predicted, and a transmission antenna weightcan be generated.

The present invention is characterized in that the adaptive transmissionunit has: L adaptive transmission sub-blocks which receive Ltransmission antenna weights which are outputs from the L transmissionantenna weight control units and a transmission signal and which outputN antenna transmission signals for forming a directivity pattern havinga gain in a user direction on the basis of the transmission antennaweights and transmitting a desired wave signal; and N adders forsynthesizing the antenna transmission signals every antenna to output Ncombining antenna signals.

According to the present invention, a delay operation in transmission isnot required to cause a mobile station to perform RAKE reception.

Each of the adaptive transmission sub-blocks according to the presentinvention is characterized by having: a transmission weighting combiningunit which receives the transmission antenna weight and the transmissionsignal to form a transmission directivity pattern; and N spreading meansfor performing spectrum spreading to each of the N antenna transmissionsignals by using a pseudo random code of a desired wave signal.

According to the present invention, directivity control is performed,and spectrum spreading is performed to the N antenna transmissionsignals.

Furthermore, the transmission weighting combining unit according to thepresent invention is characterized by having N complex multipliers whichreceive the transmission antenna weight and the transmission signal tomultiply the transmission signal by N complex transmission antennaweights, respectively.

According to the present invention, since an actual transmissiondirection is predicted from an estimation value of an arrival direction,the transmission direction can be made almost equal to the arrivaldirection of an actual reception signal.

If the present invention, more specifically, will be described withrespect to FIGS. 1A and 1B (to be referred to as FIG. 1 hereinafter),the adaptive transceiver device has first to Mth path adaptive receptionsub-blocks (41 to 4M in FIG. 1), first to Mth transmission antennaweight control units (81 to 8M in FIG. 1), and first to Lth adaptivetransmission sub-blocks (101 to 10M in FIG. 1) for each user.

In the adaptive transceiver device according to the present invention,as is apparent from the disclosure, an arrival direction of a path isestimated from a reception antenna weight. Therefore, with respect to anadaptive reception unit for performing control based on the MMSEstandards, a path arrival direction of a desired wave signal can beeasily estimated. By predicting a transmission direction from theestimated arrival direction, a present arrival direction can bepredicated by using a past arrival direction which is estimated latebecause of the control of the adaptive reception unit.

BRIEF EXPLANATION OF THE DRAWINGS

FIGS. 1A and 1B (to be referred to as FIG. 1 hereinafter) are blockdiagrams showing an embodiment of a k-th user adaptive transceiverdevice according to the present invention.

FIG. 2 is a block diagram showing an m-th path adaptive receptionsub-block of the k-th user adaptive transceiver device according to thepresent invention.

FIG. 3 is a block diagram showing a first transmission antenna weightcontrol unit of the k-th user adaptive transceiver device according tothe present invention.

FIG. 4 is a block diagram showing another embodiment of the firsttransmission antenna weight control unit of the k-th user adaptivetransceiver device according to the present invention.

FIG. 5 is a graph showing an operation of a first transmission directionprediction circuit of the k-th user adaptive transceiver deviceaccording to the present invention.

FIG. 6 is a block diagram showing a first adaptive transmissionsub-block of the k-th user adaptive transceiver device according to thepresent invention.

FIGS. 7A and 7B are block diagrams showing an embodiment of aconventional k-th user adaptive transceiver device.

FIG. 8 is a block diagram showing an m-th path adaptive receptionsub-block of the conventional k-th user adaptive transceiver device.

FIG. 9 is a block diagram showing an m-th path adaptive transmissionsub-block of the conventional k-th user adaptive transceiver device.

FIG. 10 is a block diagram showing an embodiment of a conventional k-thuser adaptive receiver device.

FIG. 11 is a block diagram showing an m-th path adaptive receptionsub-block of the conventional k-th user adaptive transceiver device.

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiments of the present invention will be described below withreference to the accompanying drawings. In this case, an adaptivetransceiver device (CDMA adaptive transceiver device) in which amultiplexed signal is a code division multiple signal, the number oftransmission/reception antenna is set to be N (N is an integer which isequal to or larger than 1), the number of users is set to be K (K is aninteger which is equal to or larger than 1), the number of receptionmulti-paths per user is set to be M (M is an integer which is equal toor larger than 1), and the maximum transmission count is set to be L (Lis equal to or larger than 1 and which is equal to or smaller than M)will be described below.

Referring to FIG. 1, a k-th user adaptive transceiver device accordingto the present invention is constituted by a first path search circuit1, a first k-th user adaptive reception unit 2, a reception antennaweight selection circuit 7, first transmission antenna weight controlunits 81 to 8M, and a k-th user adaptive transmission unit 9. Here, kindicates an arbitrary user number in the number of all users K.

The N antenna reception signals 1 to N are a desired wave signalreceived by N antennas arranged and closed to each other such that thereception signals are correlated to each other and signals obtained byperforming code multiplexing to a plurality of interference wavesignals. The following processes are digitally performed in a base band.Therefore, it is assumed that the frequencies of the N antenna receptionsignals 1 to N are converted from a radio band to a base band, that theN antenna reception signals 1 to N are subjected to analog/digitalconversion to be converted into base band signals serving as binarysignals.

The first path search circuit 1 calculates pieces of path levelinformation P1 to PM which are reception powers of the paths of adesired wave signal of the k-th user and pieces of path delay timeinformation D1 to DM which are delay times of multi-paths from thereception signals performed code multiplexing by the plurality of usersignals.

In this case, when reception antenna elements have omnidirectionalproperties (non-directivity), path searching is performed by using anantenna reception signal from any one of the antenna elements. On theother hand, when the reception antenna elements have directivity,another non-directional reception antenna for path searching isprepared, or reception weighting combining is performed to receptionantenna signals from the plurality of reception antenna elements. Anon-directional reception directivity pattern must be formed, and pathsearch must be performed by using the received reception signals.

The first k-th user adaptive reception unit 2 is constituted by firstdelay circuits 31 to 3M, first m-th path adaptive reception sub-blocks41 to 4M, a first adder 5, and a decision circuit 6.

Here, the first delay circuits 31 to 3M delay the N antenna receptionsignals 1 to N every multi-path on the basis of the pieces of path delaytime information D1 to DM which are outputs from the first path searchcircuit 1.

The first m-th path adaptive reception sub-blocks 41 to 4M will bedescribed later.

The first adder 5 adds outputs from the first m-th path adaptivereception sub-blocks 41 to 4M to output a k-th user demodulation signal.

The decision circuit 6 performs hard decision to an output from thefirst adder 5 to output a k-th user decision symbol.

The reception antenna weight selection circuit 7 receives M receptionantenna weights W1 to WM which are outputs from the M first m-th pathadaptive reception sub-blocks 41 to 4M, the pieces of path levelinformation P1 to PM which are outputs from the first path searchcircuit 1, a path level threshold value ΔP, and the maximum transmissioncount L, and selects selection reception antenna weights Wr1 to WrLcorresponding to L transmission paths from the M reception antennaweights W1 to WM on the basis of the pieces of path level information P1to PM, the path level threshold value ΔP and the maximum transmissioncount L.

In selection of the selection reception antenna weights Wr1 to WrL, anarrival direction of the maximum transmission count L including themaximum power path is selected as a transmission direction from arrivaldirections of reception powers within the range of the level of themaximum path to the path level threshold value ΔP. If the path levelthreshold value ΔP is not set, the L upper arrival directions of thepath level are always selected as transmission directions.

In addition, when the maximum transmission count L is set to be 1, onlythe arrival direction of the maximum power path is always selected as atransmission direction. When a plurality of transmission paths areselected, a transmission diversity effect can be obtained.

The k-th user adaptive transmission unit 9 is constituted by firstadaptive transmission sub-blocks 101 to 10L and third adders 111 to 11N.

The third adders 111 to 11N add outputs from the first adaptivereception sub-blocks 101 to 10M every antenna element, and outputs Ncombining antenna transmission signals 1 to N.

Thereafter, the N combining antenna transmission signals 1 to N aredigital/analog-converted, and frequency conversion from a base band to aradio band is performed.

The first m-th path adaptive reception sub-blocks 41 to 4M in the k-thuser adaptive receiver 2 will be described below. Referring to FIG. 2,each of the first m-th path adaptive reception sub-blocks 41 to 4M isconstituted by despreading circuits 121 to 12M, a reception weightingcombining unit 13, a demodulation unit 16, a third complex multiplier19, an error detection circuit 20, a second delay circuit 21, and areception antenna weight control circuit 22.

The first m-th path adaptive reception sub-blocks 41 to 4M receive theantenna reception signals 1 to N and a k-th user decision symbol whichis an output from the decision circuit 6.

The despreading circuits 121 to 12N perform correlative calculationbetween the antenna reception signals 1 to N and the pseudo random codeCk of the k-th user. When it is determined that the pseudo random codeCk is a complex code consisting of two codes CkI and CkQ which areorthogonal to each other, each of the despreading circuits 121 to 12Ncan be realized by one complex multiplier and an averaging circuitoperating over a symbol section. Each of the despreading circuits 121 to12N can be realized by a transversal filter configuration using thepseudo random code Ck as a tap weight.

The reception weighting combining unit 13 is constituted by the firstcomplex multipliers 141 to 14N and a second adder 15. Outputs from thedespreading circuits 121 to 12N are multiplied by the reception antennaweights Wm1 to WmN by the first complex multipliers 141 to 14N and addedto each other, so that a signal received by an antenna directivitypattern inherent in the m-th path is generated.

The demodulation unit 16 is constituted by a transmission pathestimation circuit 17 and a second complex multiplier 18. An outputobtained such that an output from the reception weighting combining unit13 is multiplied by the complex conjugate of a transmission pathestimation output obtained by causing the transmission path estimationcircuit 17 to estimate a transmission path is used as an output from thefirst m-th path adaptive reception sub-block 4 m. Outputs from the firstm-th path adaptive reception sub-block 4 m are added to each other bythe other first path adaptive reception sub-block 41 to the Mth pathadaptive reception sub-block 4M and the first adder 5, and a resultantvalue is used as a demodulation signal of the k-th user.

The third complex multiplier 19 multiplies a k-th user decision symbolby the transmission path estimation output.

Here, when the k-th user decision symbol is multiplied by thetransmission path estimation values of the respective paths, onlycomponents related to the phases of the estimation values can also bemultiplied, amplitudes calculated by another means may also bemultiplied. Another means indicates such a means that a reception poweris measured to calculate an amplitude.

The error detection circuit 20 calculates the difference between anoutput from the third complex multiplier 19 and an output from thereception weighting combining unit 13 to detect a reception antennaweight control error em.

The second delay circuit 21 delays outputs from the despreading circuits121 to 12N depending on process times of the reception weightingcombining unit 13, the demodulation circuit 16, the error detectioncircuit 20, and the like.

The reception antenna weight control circuit 22 calculates receptionantenna weights Wm1 to WmN from a reception antenna weight control errorem and an output from the second delay circuit 21. Here, the m-threception antenna weights Wm1 to WmN are adaptively controlled by theMMSE standards such that the mean square of the reception antenna weightcontrol error em is minimized. The reception antenna weights Wm1 to WmNobtained by using an LSM algorithm as an update algorithm having a smallamount of operation are expressed by:Wm(i+1)=Wm(i)+μr(i−Ddem)em*(i)  (1)where, Wm(i) (row vector having N elements) is a reception antennaweight of an ith symbol in the m-th path of the k-th user; r(i) (rowvector having N elements) is an antenna reception signal; μ is a stepsize; and Ddem is a delay time given by the second delay circuit 21.Reference symbol indicates a complex conjugate.

The reception antenna weights Wm1 to WmN are updated by equation (1)every symbol. The step size which is a coefficient of an amount ofchange when the reception antenna weights Wm1 to WmN are updated ischaracterized as follows. That is, when the step size μ is large,convergence to the reception antenna weights Wm1 to WmN for forming anoptimum directivity pattern becomes fast, but the accuracy and stabilityof adaptation are degraded. When the step size μ is small, the accuracyand stability of adaptation are excellent, but convergence becomes slow.A method which adaptively changes the step size to obtain a sufficientconvergence speed and sufficiently accurate and stable adaptation isalso included in the present invention.

Here, in the convergence process of adaptive control, a known symbol mayalso be used in place of a decision symbol.

A first transmission antenna weight control unit 81 will be describedbelow with reference to FIG. 3. The first transmission antenna weightcontrol unit 81 receives a first from the reception antenna weightselection circuit 7, and is constituted by a first arrival directionestimation unit 23, a first transmission direction prediction circuit29, and a first transmission antenna weight generation circuit 30.

The first arrival direction estimation unit 23 is constituted by anarrival direction generation circuit 24, a steering vector generationcircuit 25, a correlative calculation circuit 26, a maximum valuedetection circuit 27, and a switching circuit 28. The first arrivaldirection estimation unit 23 receives the selection reception antennaweight Wr1 which is an output from the reception antenna weightselection circuit 7.

The arrival direction generation circuit 24 sweeps arrival directions ofreception signals over all the directions. The steering, vectorgeneration circuit 25 calculates an antenna weight (steering vector) forforming a directivity pattern having a maximum antenna gain with respectto an arrival direction which is an output from the arrival directiongeneration circuit 24.

The correlative calculation circuit 26 calculates correlation betweenthe selection reception antenna weight Wr1 which is output from thereception antenna weight selection circuit 7 and the antenna weightwhich is an output from the steering vector generation circuit 25.

The maximum value detection circuit 27 detects the maximum value of anoutput from the correlative calculation circuit 26 with respect to allthe arrival directions which are outputs from the arrival directiongeneration circuit 24.

The switching circuit 28 switches the timings of the arrival directionswhich are outputs from the arrival direction generation circuit 24 whenthe maximum value of the output from the correlative calculation circuit26 to be detected, and outputs the arrival direction as an estimatedarrival direction θr1.

The operation of the first transmission direction prediction circuit 29is shown in FIG. 5. The first transmission direction prediction circuit29 predicts a transmission direction θr1 on the basis of the estimatedarrival direction θr1 which is an output from the first arrivaldirection estimation unit 23. In the graph, the abscissa indicates time,and the ordinate indicates angles of the estimated arrival direction,the actual arrival direction, and the prediction transmission direction.Referring to FIG. 5, the arrival direction estimation value θr1estimated from the first selection reception antenna weight Wr1 iscompared with the actual arrival direction, and adaptive delay τ occursby time required for adaptive control.

Therefore, for example, in linear prediction, when an inclination δ iscalculated from the change of time of the arrival direction estimationvalue θr1, a transmission direction prediction value θt1 is expressedby:θt 1(t)=θr 1(t)+δθ×τ  (2)where the arrival direction estimation value θt1(t) and the transmissiondirection prediction value θt1(t) are functions of time t.

Unlike the linear prediction, a method which adaptively predicts thetransmission direction prediction value θt1 such that a mean squareerror between the transmission direction estimation value θt1 and thearrival direction estimation value θr1 is possible. In this manner, whenthe transmission direction is predicted from the arrival directionestimation value, a present arrival direction can be predicted by usinga past arrival direction which is estimated late because of the controlof the adaptive reception unit.

The first transmission antenna weight generation circuit 30 calculates atransmission antenna weight (steering vector) Wt1 for forming adirectivity pattern having a gain in a transmission direction on thebasis of the prediction transmission direction θt1 which is an outputfrom the first transmission direction prediction circuit 29.

The first transmission antenna weight control unit 81 shown in FIG. 4 isan embodiment in which the reception antenna weight control circuit 22is controlled at a sufficiently high speed, and the estimated arrivaldirection θr1 estimated from the first selection reception antennaweight Wr1 is almost equal to the present arrival direction. In thiscase, the first transmission antenna weight generation circuit 30 is notrequired.

Referring to FIG. 6, each of the first adaptive transmission sub-blocks101 to 10M in the k-th user adaptive transmission unit 9 is constitutedby a transmission weighting combining unit 31 and spreading circuits 331to 33M. The first adaptive transmission sub-blocks 101 to 10M receivetransmission antenna weights Wtl to WtL which are outputs fromtransmission antenna weight generation circuits 301 to 30L, and a k-thuser transmission signal.

The transmission weighting combining unit 31 is constituted by fourthcomplex multipliers 321 to 32N. When the k-th user transmission signalis multiplied by the first transmission antenna weight Wtl (Wtl1 toWtlN), a signal transmitted by a first inherent antenna directivitypattern is generated.

The spreading circuits 331 to 33N diffuse N outputs from thetransmission weighting combining unit 31 by using a pseudo random codeCk of the k-th user to generate N antenna transmission signals 1 to N.When the pseudo random code Ck is considered as a complex codeconsisting of two codes CkI and CkQ which are orthogonal to each other,each of the spreading circuits 331 to 33N is realized by one complexmultiplier and an averaging circuit operating over a symbol section.Each of the spreading circuits 331 to 33N can also be realized by atransversal filter configuration using the code Ck as a tap weight.

In the embodiment of the present invention, the code length of thepseudo random code Ck, i.e., a spreading rate is not limited. Theadaptive receiver device according to the present invention can also beapplied to a signal having a spreading rate of 1 and multiplexed by asystem other than a code division multiple access system.

In the embodiment of the present invention, arrangement intervalsbetween the reception antennas. For example, a wavelength which is ½that of a carrier wave is used. In addition, in the embodiment of thepresent invention, the number N of reception antennas is not limited.

Furthermore, in the embodiment according to the present invention, thearrangement of the reception antennas is not limited. For example, acircular arrangement or a straight arrangement is used.

In the embodiment of the present invention, the directivity of a singlereception antenna is not limited. For example, an omni-antenna or asector antenna is used.

In addition, in the embodiment of the present invention, the number K ofusers which simultaneously receive signals and the number M ofmulti-paths of each user are not limited.

According to the present invention, in the k-th user adaptive receptionunit, since the control method based on the MMSE standards is used, adirectivity pattern which actively decreases a gain with respect to aninterference wave is formed in the reception unit of the k-th useradaptive transceiver device.

According to the present invention, there is provided a means whichestimates a path arrival direction of a desired wave signal by using areception antenna weight of the k-th user adaptive reception unit andwhich generates a transmission antenna weight on the basis of the patharrival direction. For this reason, desired wave arrival directionestimation means for calculating the transmission antenna weight of thetransmission unit of the k-th user adaptive transceiver device is notprepared independently of the reception unit.

INDUSTRIAL APPLICABILITY

As has been described above, the present invention can be applied to anadaptive transceiver device in a base station which mainly copes with aplurality of mobile stations of a mobile communication system. Sincethere is provided means which estimates a path arrival direction of adesired wave signal by using a reception antenna weight of the k-th useradaptive reception unit and which generates a transmission antennaweight on the basis of the path arrival direction, a merit of thepreaent invention is that a desired wave arrival direction estimationmeans for calculating the transmission antenna weight of thetransmission unit of the k-th user adaptive transceiver device does notneed to be prepared independently of the reception unit.

The adaptive transceiver device according to the present invention canbe used in the equipment of a base station using the cdma-One system orthe W-CDMA system, and can make a transmission power constant in apredetermined direction by weighting or the like depending on receptionsensitivity.

1. An adaptive transceiver device of a CDMA (Code Division MultipleAccess) system characterized by comprising: path search means forcalculating path level information and path delay time information fromantenna reception signals; M (M is a positive integer) adaptivereception units for receiving N (N is a positive integer) antennareception signals, forming reception directivity patterns each having again in the direction of a desired wave signal every path delay time,receiving the desired wave signals, and suppressing interference wavesignals; reception antenna weight selection means for selectingreception antenna weights for L (L is an integer equal to or smallerthan M) transmission paths among M reception antenna weights by usingthe path level information; L transmission antenna weight control unitsfor determining transmission antenna weights for forming transmissiondirectivity patterns by using outputs from the reception antenna weightselection means; and an adaptive transmission unit for forming thetransmission directivity pattern having a gain in a user direction byusing the transmission antenna weight which is an output from thetransmission antenna weight control unit and outputting N combiningantenna transmission signals for transmitting the desired wave signal,the adaptive transmission unit having L adaptive transmission sub-blockswhich receive L transmission antenna weights which are outputs from theL transmission antenna weight control units and a transmission signaland which output N antenna transmission signals for forming adirectivity pattern having a gain in a user direction on the basis ofthe transmission antenna weights and transmitting a desired wave signal.2. The adaptive transceiver device according to claim 1, characterizedin that the adaptive reception unit has: M delay means which receive theN antenna reception signals and the path delay time information which isan output from the path search means and which match timings dependingon the path delay times of M multi-paths; M adaptive receptionsub-blocks for forming the reception directivity patterns having gainsin the directions of the M multi-paths, suppressing the interferencewave signal, and receiving and demodulating the desired wave signal; anadder for synthesizing M demodulation signals; and decision means forperforming hard decision to output a decision symbol.
 3. The adaptivetransceiver device according to claim 2, characterized in that theantenna reception signal is a code division multiple access (CDMA)signal, and each of the M adaptive reception sub-blocks has: Ndespreading means which receive the N antenna reception signals and thedecision symbol and performs despreading to each of the antennareception signals by using a pseudo random code of the desired wavesignal; a reception weighting combining unit for forming the receptiondirectivity pattern; a demodulation unit for performing the transmissionpath estimation; a multiplier for multiplying the decision symbol by acomplex transmission path estimation value which is an output from thedemodulation unit to cancel a phase change caused by carrier wave phasesynchronization; error detection means for subtracting each output fromthe despreading means from an output from the multiplier; delay meansfor delaying outputs from the N despreading means depending on theprocess times of the reception weighting combining means, thedemodulation means; and reception antenna weight control means foroutputting the reception antenna weight on the basis of the minimum meansquare error (MMSE) standards such that the average power of thereception antenna weight control error is minimized by using an outputfrom the delay means and the reception antenna weight control error. 4.The adaptive transceiver device according to claim 3, characterized inthat the reception weighting combining unit has: N complex multiplierswhich receive the N antenna reception signals and the reception antennaweights and which multiply the reception signals by N complex receptionantenna weights; and an adder for synthesizing respective outputs fromthe N complex multipliers.
 5. The adaptive transceiver device accordingto claim 3, characterized in that the demodulation means has:transmission path estimation means which receives an output from theweighting combining unit to estimate the amplitude and the phase of acarrier wave; complex conjugate operation means for calculating acomplex conjugate of complex transmission path estimation values whichare output from the transmission path estimation means; and a multiplierfor multiplying an output from the complex conjugate operation means byan output from the despreading means to perform carrier wave phasesynchronization and, at the same time, to perform weighting forsynthesizing a maximum ratio.
 6. The adaptive transceiver deviceaccording to claim 4, characterized in that the demodulation means has:transmission path estimation means which receives an output from theweighting combining unit to estimate the amplitude and the phase of acarrier wave; complex conjugate operation means for calculating acomplex conjugate of complex transmission path estimation values whichare output from the transmission path estimation means; and a multiplierfor multiplying an output from the complex conjugate operation means byan output from the despreading means to perform carrier wave phasesynchronization and, at the same time, to perform weighting forsynthesizing a maximum ratio.
 7. The adaptive transceiver deviceaccording to claim 1, characterized in that the reception antenna weightselection means receives M reception antenna weights which are outputsfrom the M adaptive reception sub-blocks, path level information whichis an output from the path search means, a path level threshold value,and a maximum transmission count Lmax, and selects a selection receptionantenna weight corresponding to L paths the number of which is notlarger than the maximum transmission count Lmax and which has a levelset within the range of the level of the maximum path to the path levelthreshold value from the M reception antenna weights.
 8. The adaptivetransceiver device according to claim 1, characterized in that thetransmission antenna weight control unit has: an arrival directionestimation unit which receives the selection reception antenna weight toestimate an estimated arrival direction from the election receptionantenna weight; and a transmission antenna weight generation means forcalculating a transmission antenna weight for forming a directivitypattern having a gain in the estimated arrival direction which is anoutput from the arrival direction estimation unit.
 9. The adaptivetransceiver device according to claim 1, characterized in that thetransmission antenna weight control unit has: an arrival directionestimation unit which receives the selection reception antenna weight toestimate an estimated arrival direction from the selection receptionantenna weight; transmission direction prediction means for predicting atransmission direction on the basis of the estimated arrival directionwhich is an output from the arrival direction estimation unit; andtransmission antenna weight generation means for calculating atransmission antenna weight for forming a directivity pattern having again in the prediction transmission direction which is an output fromthe transmission direction prediction means.
 10. The adaptivetransceiver device according to claim 2, characterized in that thereception antenna weight selection means receives M reception antennaweights which are outputs from the M adaptive reception sub-blocks, pathlevel information which is an output from the path search means, a pathlevel threshold value, and a maximum transmission count Lmax, andselects a selection reception antenna weight corresponding to L pathsthe number of which is not larger than the maximum transmission countLmax and which has a level set within the range of the level of themaximum path to the path level threshold value from the M receptionantenna weights.
 11. The adaptive transceiver device according to claim2, characterized in that the transmission antenna weight control unithas: an arrival direction estimation unit which receives the selectionreception antenna weight to estimate an estimated arrival direction fromthe selection reception antenna weight; and transmission antenna weightgeneration means for calculating a transmission antenna weight forforming a directivity pattern having a gain in the estimated arrivaldirection which is an output from the arrival direction estimation unit.12. The adaptive transceiver device according to claim 2, characterizedin that the transmission antenna weight control unit has: an arrivaldirection estimation unit which receives the selection reception antennaweight to estimate an estimated arrival direction from the selectionreception antenna weight; transmission direction prediction means forpredicting a transmission direction on the basis of the estimatedarrival direction which is an output from the arrival directionestimation unit; and transmission antenna weight generation means forcalculating a transmission antenna weight for forming a directivitypattern having a gain in the prediction transmission direction which isan output from the transmission direction prediction means.
 13. Theadaptive transceiver device according to claim 11, characterized in thatthe arrival direction estimation unit has: arrival direction generationmeans which receives the selection reception antenna weight to sweeparrival directions over all the directions; steering vector generationmeans for calculating an antenna weight for forming a directivitypattern of a maximum antenna gain in the arrival direction; correlativecalculation means for calculating a correlation between the selectionreception antenna weight and an antenna weight which is an output fromthe steering vector generation means; maximum value detection means fordetecting the maximum value of outputs from the correlative calculationmeans with respect to all the arrival directions; and switching meansfor outputting the arrival direction at a point of time at which themaximum value is detected as an estimated arrival direction.
 14. Theadaptive transceiver device according to claim 12, characterized in thatthe transmission direction prediction means predicts a present arrivaldirection by using a past arrival direction which is estimated latebecause of the control of the adaptive reception unit.
 15. The adaptivetransceiver device according to claim 1, characterized in that theadaptive transmission unit has: N adders for synthesizing the antennatransmission signals every antenna to output N combining antennasignals.
 16. The adaptive transceiver device according to claim 2,characterized in that the adaptive transmission unit has: L adaptivetransmission sub-blocks which receive L transmission antenna weightswhich are outputs from the L transmission antenna weight control unitsand a transmission signal and which output N antenna transmissionsignals for forming a directivity pattern having a gain in a userdirection on the basis of the transmission antenna weights andtransmitting a desired wave signal; and N adders for synthesizing theantenna transmission signals every antenna to output N combining antennasignals.
 17. The adaptive transceiver device according to claim 15,characterized in that each of the adaptive transmission sub blocks has:a transmission weighting combining unit which receives the transmissionantenna weight and the transmission signal to form a transmissiondirectivity pattern; and N spreading means for performing spectrumspreading to each of the N antenna transmission signals by using apseudo random code of a desired wave signal.
 18. The adaptivetransceiver device according to claim 17, characterized in that thereception antenna weight is updated every symbol, and the step ofupdating the reception antenna weight is determined depending on thedegree of convergence of the reception antenna weight.
 19. The adaptivetransceiver device according to claim 18, characterized in that thetransmission weighting combining unit has N complex multipliers whichreceive the transmission antenna weight and the transmission signal andwhich multiply the transmission signal by N complex transmission antennaweights.